The field of the invention is collapsible furniture.
Folding chairs are relatively popular, in part because they can be stored at considerably reduced space requirements when compared to non-folding chairs. Exemplary folding chairs with rigid arm rests and seat support rods are described in U.S. Pat. No. 4,613,185 to Marchesini et al. (Sep. 23, 1986), U.S. Pat. No. 5,899,525 to Tseng (May 4, 1999), U.S. Pat. No. 5,947,553 to Tseng (Sep. 7, 1999), and U.S. Pat. No. 6,062,639 to Hill (May 16, 2000), all of which are incorporated by reference herein.
Nevertheless, previously known folding chairs still take up a relatively large space when folded, since the dimension of the folding chair is generally reduced only along one space coordinate (e.g., reduced length). To further reduce the space requirement, collapsible chairs have been developed in which further size reduction is achieved by folding the chair along at least two space coordinates (e.g., length and width). Various collapsing chairs are known in the art.
In U.S. Pat. No. Des 247,618 (Mar. 28, 1978), for example, Sparkes describes a collapsible stroller with rigid armrests and seat support rods that is first folded in a front to back motion and then folded in a side-to-side motion. Although Sparkes"" stroller provides substantial space saving over non-collapsible strollers, the collapsing is relatively cumbersome since both halves of the chair have to be rotated relative to each other. Improved collapsibility can be achieved by including a detachable connector element into a structure that couples foldable halves of the stroller as described in U.S. Pat. No. 4,317,581 to Kassai (Mar. 2, 1982). Uncoupling of the detachable element advantageously simplifies side-to-side folding of the stroller. However, Kassai""s stroller nevertheless requires at least two folding operations to collapse the stroller.
To avoid at least some of the problems associated with multiple operations of collapsible chairs, Mann describes in U.S. Pat. No. 5,058,950 (Oct. 22, 1991) the use of hinges in both armrests and seat support rods. Mann""s chair can be collapsed in a single side-to-side and front-to-back motion, however, the hinges in the armrests may be uncomfortable for at least some of the users. Moreover, due to the particular configuration of movable elements in the chair, front and back seat support rods are perpendicular to the legs of a person sitting in the chair, which will likely restrict blood flow in the legs of almost all users over a prolonged period.
Although there are various collapsible chairs with rigid armrests known in the art, all or almost all of them suffer from one or more disadvantages. Therefore, there is a need to provide improved methods and apparatus for collapsible chairs with rigid armrests.
The present invention is directed to collapsible chairs with rigid armrests, and especially to those in which the slid armrest is slidably coupled to the front leg, rear leg, and/or back support rod.
In one aspect of the inventive subject matter, contemplated chairs include a front leg rotatably coupled to a rear leg, a back support rod pivotably coupled to the rear leg, a seat coupled to the rear leg, and a rigid armrest slidably coupled to the front leg, such that the chair collapses in a single movement. Such chairs may further comprise a first cross brace and a second cross brace, wherein the first cross brace is coupled to the front leg and a second rear leg, and wherein the second cross brace is coupled to the rear leg and a second seat support rod such that the chair collapses in a single movement in which the front legs approximate each other as the front legs and the rear legs pivot towards each other.
In still further aspects of contemplated chairs, an auxiliary rod may be rotatably coupled to the rear leg and slidably and rotatably coupled to the front leg, wherein the auxiliary rod may further engage with the first cross brace when the chair is in an open configuration. The back rest is preferably coupled to the back support rod (and may be contiguous with the seat), while the armrest in preferred chairs has an arcuate shape.
In another aspect of the inventive subject matter, contemplated chairs may include a pair of front legs, a pair of rear legs, a pair of back support rods, a pair of rigid arm rests, a first pair of cross braces, and a second pair of cross braces, wherein each of the front legs is rotatably coupled to each of the rear legs, respectively, wherein each of the back support rods is pivotably coupled to each of the rear legs, respectively, wherein each of the rigid armrests is slidably coupled to each of the front legs. Such chairs may further include a seat coupled to the rear legs, and a back rest coupled to the back support rods, wherein the seat and the back rest are contiguous, wherein one cross brace of the first pair of cross braces is rotatably coupled to one of the front legs and rotatably coupled to one of the rear legs, and wherein one cross brace of the second pair of cross braces is rotatably coupled to one of the rear legs and rotatably and slidably coupled to one of the back support rods.
Various objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.